Venezuelan President Nicolas Maduro on Wednesday called U.S. Vice President Mike Pence a “viper” and vowed to defeat what he called Washington’s attempts to force him from power.

Pence, who arrived in Ecuador on Wednesday as part of a tour of South America, is seeking to boost regional pressure on Venezuela following Maduro’s reelection in May in a vote that the United States said was fraudulent.

Even after President Donald Trump’s order putting a temporary halt to the separation of families arrested for crossing the border illegally, the pressure is on Republicans in Congress to come up with a solution.

“Every time the poisonous viper Mike Pence opens his mouth, I feel stronger,” the socialist leader said in a televised speech. “We have defeated you and we are going to defeat (you) wherever you are.”

Maduro insists that the United States is seeking to overthrow his government in order to seize the OPEC nation’s oil and mineral wealth, and accuses Washington of leading an “economic war” against the country.